Micrometer caliper with ball pivot and cam



July 3, 1951 H. PICKETT MICROMETER CALIPER WITH BALL PIVOT AND CAM Filed Deo. 10, 1947 In ventor Patented July 3, 1951 MICROMETER CALIPER WITH BALL PIVOT AND CAM Herbert Pickett, Houston, Tex.

Application December 10, 1947, Serial No. 790,857

2 Claims.

The present invention relates to certain new and useful improvements in measuring instruments such as dual leg-equipped dividers, compasses and calipers and has reference in`particular to micrometer-calipers used, generally speaking, for accurately measuring and determining inside and outside diameters.

An object of the invention is to structurally, functionally and otherwise improve on instruments in the stated category by adopting and using novel structural adaptations which coordinate their functions in providing eicient and structurally distinct micrometer-calipers susceptible of use with finesse and which are reliably employable in accomplishing wanted ends with requisite precision.

Another object of the invention is to provide a relatively simple frame, a pair of complemental calipering legs pivotally mounted on said frame, and micrometer type means also on the frame and mechanically coacting with inner end portions of the legs to precisely control the operation and functioning of said legs.

Other objects and advantages of the invention will become more readily apparent from the following description and the accompanying illustrative drawings.

In the drawings, wherein like numerals are employed to designate like parts throughout the views:

Figure 1 is a side elevational view of micrometer-calipers constructed in accordance with the principles of the instant invention;

:Figure 2 is a central longitudinal sectional View taken on the line 2-2 of Figure 1, looking in the direction of the arrows;

Figure 3v is a sectional view at right angles to Figure 2, the section'being on the line 3-3 of Figure 1, also looking in the direction of the arrows;

Figure 4 is a fragmentary elevational view;

Figure 5 is a fragmentary elevational view showing certain of the essential parts;

Figure 6 is a fragmentary elevational view of the parts assembled and focusing attention on the micrometer means;

Figure '7 is a fragmentary horizontal section taken on the line I-'I of Figure l, looking in the direction of the arrows. f

Referring now to the drawings by distinguishing reference numerals and complemental lead lines it will be seen that the aforementioned frame is denoted by the numeral 8 and is of inverted U-shaped form, the parallel limb portions being denoted by the numerals 9 and these having their free ends connected one with the other by way of a bolt or equivalent fastener I0. The bight portion II is provided at a point centrally between the limb portions with an integral stud I2 and this is vaxially socketed and screw threaded as at I3.V On its exterior surfaces I provide graduations I4 with appropriate ordinals providing suitably functioning scales.

Before describing the so called micrometer mechanism I will cover the calipering legs I5, said legs, in the drawings, being shown for outside diameter measurement purposes. however, by properly redesigning the legs they may then be employed for inside diameter measurements. siderably widened, as seen in the drawings and have assembling and stabilizing adapters I6 of arcuate form connecting respectively with predetermined marginal portions of assembling disks I'I. The disks I of the respective legs are disposed in spaced parallelism between the limb` portions 9 of the U-frame and are provided in their outer surfaces and at their immediate centers with depressions which are lined up with similar depressions in the limb portions to accommodate motion transmitting or actuator balls 20. The balls 20 t and are assembled in semispherical depressions or recesses 2| formed in" opposite faces of a rectangular motion transmit-v ting and actuating block 22. The block is a reciprocatory unit and includes a reduced necklike extension which may be referred to as a relatively movable stud 23 since it lines up with the aforementioned relatively stationary stud I2. The stud 23 is also provided with a central screw threaded socket 24 for coaction with the socket I3. What is more, it is provided with calibrations 25 and suitable coacting ordinals.

A thumb wheel is denoted by the numeral 26 and this has its marginal portion milled or suitably knurled for convenient gripping and turning. The grip also carries axially alined right and left feed screws 2l and 28 and these are threaded into the respective sockets I3 and 24 which are correspondingly threaded. Attached permanently to the wheel 26 and surrounding Obviously,

The actuable ends of the legs are coneach stud is a sleeve and the sleeves are respectively denoted by the numerals 29 and 30 and have bevelled portions 3l which are properly graduated and marked to provide rotary micrometering scales and these coact with the reciproeating micrometer scales I4 and 25 on the aforementioned studs l2 and 23. It follows that we thus have manually operable mechanical means with the parts effectively cooperating and provided with coacting indicating scales, whereby to provide micrometer means between the frame 8 and actuator unit 22, the latter, by way of the cam grooves I9 and coacting balls 20 converting rotary motion into reciprocatory motion and serving to move the legs l5 toward and from each other and at the same time providing accurate measuring facilities. No doubt, the views of the drawings, read singly and collectively and in conjunction with the description will enable the reader to understand the construction and operation of the instrument.

Precise directions for use and examples of various shop practices already well yknown to those skilled in the art to which the invention appertains need not, it is believed, be herein in cluded.

A careful consideration of the foregoing description in conjunction with the invention as illustrated in the drawings will enable the reader to obtain a clear understanding and impression of the alleged features of merit and novelty sumcient to clarify the construction of the invention as hereinafter claimed.

Minor changes in shape, size, materials and rearrangement of parts may be resorted to in actual practice so long as no departure is made from the invention as claimed. Y

Having described the invention, what is claimed as new is:

'1. A measuring instrument of the Aclass shown if and described comprising a frame means embodying spaced parallelresilient limbs, a pair of complemental calipering legs having spaced parallel heads'at corresponding ends, one head being disposed in rotary wiping contact with the inner surface of one limb and the other head being disposed in rotary wiping contact with the corresponding inner surface of the remaining limb, the outside surfaces of said heads having median depressions, the coacting inside surfaces of said limbs having corresponding depressions respectively aligned with said iirst named depressions, anti-friction balls removably seated, one ball in each coacting pair of opposed depressions and pivotally connecting said heads with said limbs, a reciprocable actuator unit fitted slidably between the opposed inner surfaces of said heads, manually adjustable means between the frame means and actuator unit for regulating the latter, and camming means interposed between said actuator unit and inside surfaces of said heads so that by reciprocating the actuator unit in relation to the heads, said calipering legs are opened and closed.

2. A measuring instrument of the class shown and described comprising a frame embodying spaced parallel resilient limbs connected at corresponding ends and having their opposite ends free and movable toward and from each other, a pair of complemental calipering members provided at corresponding ends with spaced parallel disk-like heads, said heads having their respective outer surfaces in rotary wiping contact with the adjacent inner surfaces of the respective coacting Ilimbs .and being centrally pivoted on said limbs, the adjacent free ends of said limbs projecting beyond the marginal edge portions of said heads and being bolted together, an

actuator unit .rectangular in cross section and reciprocable in sliding contact between saidheads, the inner opposed surfaces of said heads having complemental camming grooves, the coacting surfaces of said actuator having semispherical recesses aligned and cooperable with said grooves, there being one groove and one co-acting recess on one side of said actuator unit and one groove and one recess on the opposite ide of said actuator unit, an anti-friction ball tted into each groove and its coacting recess to provide cam operating connections between the heads and unitv for opening and closing said-members, and means interposed between said frame means and actuator foradjusting the latter.

HERBERT v.'tICKlilIT..

' REFERENCESY CITED The following references are of record in theA Number Name YDate l 205,543 Grigg July 2, 187,8 559,559 Worthen Mayi5, 1896 762,786 West lJune 14,1904 794,094 Glove AJuly 4, 1905 844,772 Bernegau Feb. 19, 1707 854,586 Mayer May 21, 1907 890,590 Anderson June 16, 1908 1,267,946 Wester May 28, 1918 1,343,664 Dieckmann June 15, 1920 1,382,628 Daniels June 28, 1921 1,479,598 ,Y Garcia Jan. 1, 1924 1,503,934 Akashi Aug. 5, 1924 1,506,704 Williamson Aug.Y .26, 1924 2,344,837 "Tarket Mar; 2l, 1944 

